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Slope or the landing board 0° to 60°, but better 60°

Landing is tricky: hit the ground too fast and you will crash and burn; too slow and you may stall and fall. Bees manage their approach by monitoring the speed of images moving across their eyes. By slowing so that the speed of the looming landing pad's image on the retina remains constant, bees manage to control their approach. But what happens in the final few moments before touch down? And how do bees adapt to landing on surfaces ranging from the horizontal to upside-down ceilings? Flies land on a ceiling by simply grabbing hold with their front legs and somersaulting up as they zip along, but a bee's approach is more sedate. Mandyam Srinivasan, an electrical engineer from the Queensland Brain Institute, The University of Queensland and the Australian Research Council's Vision Centre, knew that bees must be doing something different from daredevil flies. Curious to know more about bee landing strategies Srinivasan teamed up with Carla Evangelista, Peter Kraft, and Judith Reinhard from the University of Queensland, and Marie Dacke, visiting from Lund University. The team used a high-speed camera to film the instant of touch down on surfaces at various inclinations and publish their discoveries about bee landing tactics in The Journal of Experimental Biology on December 28 2009 at http://jeb.biologists.org.
First the scientists built a bee-landing platform that could be inclined at any angle from horizontal to inverted (like a ceiling), then they trained bees to land on it and began filming. Having collected movies of the bees landing on surfaces ranging from 0deg. to 180deg., and every 10deg. inclination between, Evangelista began the painstaking task of manually analyzing the bees landing strategies, and saw that the bees' approach could be broken down into 3 phases.
Initially the bees approached from almost any direction and at any speed, however, as they got closer to the platforms, they slowed dramatically, almost hovering, until they were 16mm from the platform when they ground to a complete halt, hovering for anything ranging from 50ms to over 140ms. When the surface was horizontal or inclined slightly, the bees' hind legs were almost within touching distance of the surface, so it was simply a matter of the bee gently lowering itself and grabbing hold with its rear feet before lowering the rest of the body.
However, when the insects were landing on surfaces ranging from vertical to 'ceilings', their antennae were closest to the surface during the hover phase. The team saw that the antennae grazed the surface and this contact triggered the bees to reach up with the front legs, grasp hold of the surface and then slowly heave their middle and hind legs up too. "We had not expected the antennae to play a role and the fact that there is a mechanical aspect of this is something that we hadn't thought about," admits Srinivasan.
Looking at the antennae's positions, the team realized that in the final stages as the insects approached inverted surfaces, they held their antennae roughly perpendicular to the surface. "The bee is able to estimate the slope of the surface to orient correctly the antennae, so it is using its visual system," explains Srinivasan. But this is surprising, because the insects are almost completely stationary while hovering and unable to use image movement across the eye to estimate distances. Srinivasan suspects that the bees could be using stereovision over such a short distance, and is keen to test the idea.
Finally, the team realized that bees are almost tailor made to land on surfaces inclined at angles of 60deg. to the horizontal. "When bees are flying fast their bodies are horizontal, but when they are flying slowly or hovering their abdomen tilts down so that the tips of the legs and antennae lie in a plane that makes an angle of 60deg." explains Srinivasan: so the legs and antennae all touch down simultaneously on surfaces inclined at 60 deg. "It seems like they are adapted to land on surfaces tilted to 60deg. and we are keen to find out whether many flowers have this natural tilt," says Srinivasan.
Srinivasan is optimistic that he will eventually be able to use his discoveries in the design of novel flight control systems. Journal of Experimental Biology

Re: Slope or the landing board 0° to 60°, but better 60°

Just wondering if bees choose trees that have entrance holes with that angle on them?? Seems to me if it was important to the bees, they would, and they are a pretty smart at existing. IMO that was a tremendous amount of money and effort spent that could have been spent on important stuff.

The biggest problems on earth that bees have are human created. Lets work on that, instead.

Re: Slope or the landing board 0° to 60°, but better 60°

Re: Slope or the landing board 0° to 60°, but better 60°

I wouldn't change my plans. And by my plans, I mean not having a landing board at all.

60º or 0º, I don't really think it matters. The bees may fly at slow speeds equal to 60º, and landing on a board that is 60º may end up saving them energy. However, the amount of energy required to correct a bees body from 60º to 0º, even a million times, doesn't really make much of a quantitative outcome in the amount of honey the bees produce, or the average life span. And it certainly doesn't justify the expense of the landing board, or the amount of energy you expel in building, painting, hauling, ect. the landing board around.

Re: Slope or the landing board 0° to 60°, but better 60°

" IMO that was a tremendous amount of money and effort spent that could have been spent on important stuff"
This is what a rich country like Australia can spend money on. Interesting. On the other hand funding to eradicate the Asian Bee has just been discontinued.
Maybe we could afford to do both?

Re: Slope or the landing board 0° to 60°, but better 60°

Originally Posted by max2

" IMO that was a tremendous amount of money and effort spent that could have been spent on important stuff"
This is what a rich country like Australia can spend money on. Interesting. On the other hand funding to eradicate the Asian Bee has just been discontinued.
Maybe we could afford to do both?

I think that the global context of this paper was trying to improve tactics of landing for helicopter and space shuttles meetings, the conclusions about bees were a side effect.